The invention relates to a device for operating a parking lock of a motor vehicle, wherein the parking lock includes an actuatable actuator device for disengaging the parking lock against a restoring pressure and an actuatable holding device for holding the parking lock in the disengaged state.
The invention also relates to a method for operating a parking lock of a motor vehicle or in the parking lock has an actuatable actuator device for disengaging the parking lock against a restoring pressure and an actuatable holding device for holding the parking lock in the disengaged state.
Devices and methods of the above-mentioned type are known from the state-of-the-art. A parking lock serves for locking the transmission, in particular the automatic transmission of a motor vehicle, when the motor vehicle stands still so that the transmission blocks the driving wheels of the motor vehicle. It is also known to automatically engage the parking lock in dependence on different parameters in order to immobilize the motor vehicle. Thus it is known in modern motor vehicles that the parking lock is automatically engaged when the ignition key is removed from the ignition lock thereby preventing the vehicle from rolling away.
For example, from the German published application DE 196 25 091 A1 a device is known by means of which the parking lock is actuated. The parking lock includes means for engaging the parking lock and a holding device in the form of a holding magnet for holding the parking lock in the disengaged state so that the holding device prevents engagement of the parking lock. The holding magnet is controlled by a transmission control device, while the means for engaging the parking brake act in response to signals from the ignition lock, the vehicle speed and the rotational speed of the motor. The known device has the disadvantage that when the transmission control device fails, engagement of the parking lock cannot be prevented.
The invention is thus based on the object to create a device and a method which enable in a simple manner to improve the safety and functionality of the parking brake.